I briefly mentioned this in N Ellingworth's Building a Guitar thread and thought I'd open a new thread for this subject.

The idea is to build an Infinity Sustainer for my guitar, this is basically an E-Bow type device fitted into the body near the neck that excites all six strings. This is not a new idea, it was mentioned in E-Bow's original patent application and Fernandez and Kramer built several guitars with built-in sustainers, but they are expensive.

Since this project involves modifying the guitar (and I don't know whether it will work yet) I am going to be making these mods to a cheap Fender Squier.

The principal is simple: sound from the pickups is amplified and used to drive a coil that excites the strings. I intend to wind my own driver coil for this based around a bare Fender-style pick-up bobbin:

This will be wound with heavier gauge wire than a normal pickup, and with fewer turns to give a lower impedance - the idea is to make the equivalent of the voice-coil in a loudspeaker, therefore the impedance should be around 8ohms so I can drive it from a 1W amplifier that can be powered from a 9v PP3 battery:

...which may not have enough gain on its own, so I'll probably need a FET i/p stage for it.

Initially I will use this pickup in place of the neck pickup - once I've got it working I'll consider putting the neck pickup back and routing a new hole in the body for the sustainer. Even though it's only a £150 Squier, I'm still loathed to attack it with power tools just yet

So, the story so far: I've worked out pretty much what I want to do, ordered the pickup kit from Stewart-MacDonald and the electronics from Maplin - just waiting for the postman now.

That was one thing I was wondering: how do you keep it from feeding back like mad?

I guess you haven't used a sustainer pickup before (probably cos you play bass), but a friend of mine has one on his Jackson DK2S Pro series guitar, specifically using the Sustainiac brand.

It has 3 modes.

One allows you sustain the 'fundamental' note, the actual note you play.

The second is called Blend, which harmonics and fundamental certain notes.

The 3rd is called Harmonic, which depending on what brand of sustainer you use, makes the fundamental note swell into a 5th or octave above the fundamental note. It sounds exactly like feedback in most cases, bearing in mind I'm talking about the musical type of feedback you get from a fundamental note swelling into a feedback harmonic, as opposed to the feedback generated from noisy preamps/excessively long pedal chain which sound harsh.

There is also a control, on the Sustainiac version at least, called Intensity Control, which controls how fast the notes swell into sustained notes/feedback.

Now that you have some background in it's functions, I'll answer your question more specifically.

If you were referring to 'feedbacking like mad' as the unmusical and harsh feedback caused by noisy preamps and excessively long pedal chains that problem is tackled by noise gates/noise reducing pedal. Noise Gates/Reducers can also to some extent reduce the chances of the musical type of feedback, because most, if not all Noise gates/reducers tend to cut off a bit of the tail end of notes, reducing a notes potential sustain.

By using the fundamental mode, the note you choose to hold will not swell into a harmonic feedback, as the note you are holding will stay as the fundamental.

Obviously feedback is not easy to get at low amp volumes, so some people love the sustainiac, because it allows them to create musical feedback at low volumes, and it can even allow you to create great sounding feedback on the clean settings of your amp.

Another question that was raised was about dampening notes. Since the sustainer driver doesn't really sound effective with more than one note at a time, you have to mute the other strings, but assuming you've learnt to play guitar properly in the first place, you would have already learnt how to mute strings that you don't want to ring out anyway, using left hand or right hand techniques, or a combination of both, depending what string you are on, what you are playing etc etc.

If you try to play 6 note chords, but some strings 'win out' and keep sustaining, which from first hand experience, will be the lower, heavier strings.

You can do some cool stuff on a clean amp setting, using finger style and playing arpeggiated chords, and getting some cool sounds with the sustainer, but once you pile on the gain, typically you will only sound good using single notes, and with this much gain, the sustainer driver only really works effectively with one note at a time anyway.

Hopefully this answers a lot of questions anyone may have had about the sustainer driver pickups.

The system is in essence controlled feedback anyway - the uncontrolled issue is a question of phase and gain - it will take some experimentation, but that's half the fun

the open strings are undamped - they well hum at a harmonic of the excitation note(s) - I haven't seen a bought system that damps individual strings - obviously palm and finger muting is the key to controlling any unwanted sympathetic vibrations.

I'm not familiar with any of the existing sustainer devices such as the Sustainiac (they have stopped producing the electromagnetic version) - I imaging the different modes of operation are just varying degrees of gain and phase shift (filtering) which can be controlled by internal feedback around the drive amp, though the possibilities for electrical manipulation of this feedback signal are endless and only limited by how much electronics you can fit into the body cavity - again, this is an area for experimentation and another reason for doing this to a cheap guitar first.

I'm just not sure it's going to be easy to get it to not create the fifth. I've used an ebow a couple of times and I found that after only a few seconds of sustain the fifth and octave were louder than the main note, and that was on the normal, not-feedback mode.

I'm just not sure it's going to be easy to get it to not create the fifth. I've used an ebow a couple of times and I found that after only a few seconds of sustain the fifth and octave were louder than the main note, and that was on the normal, not-feedback mode.

As I explained my last post on this thread, using the fundamental mode will ensure the note continues to sustain purely as the fundamental note. An ebow and sustainer driver pickup really aren't the same beast.

I have been using the Sustainiac pickup fitted to my friend's Jackson DK2S Pro Series guitar since he got his guitar in May last year, and you can seriously sustain a note as long as you want without it swelling into a feedback harmonic.

I've been reading through the patent for the Sustainiac (US PAT: 5932827)...

The Sustainiac replaces the Middle Pickup with the Driver Coil, which is also used as a normal pickup when the Sustainer circuit is switched off - since this pickup has fewer turns than a standard pickup it produces a smaller signal, so a built-in pre-amp is used to match the amplitude to the other two pickups.

The Fundamental Mode is essentially feedback from the Neck Pickup fed through a wide-band filter, 480Hz to 3400Hz, (which is something like A#5 to G7). The signal from this pick up generally contains more of the fundamental and less harmonic frequencies, so when used to provide the excitation frequencies to the Driver Coil it will tend to vibrate the strings predominantly at the fundamental note.

Harmonic Mode is feedback from Bridge Pickup fed through a narrow-band filter centred on 720Hz (somewhere around F5). The signal from this pickup is rich in harmonics and so when fed to the Driver Coil will favour harmonic resonance.

Obviously "Blend" is a mix of the two and when the Sustain circuit is switched on, the middle pickup cannot be used as a source.

Both the Neck and Bridge filters remove the extremely high harmonics that would result in (electrical) instability.

The low-frequency cut-off for both is two octaves higher than the lowest note a guitar can produce and I'm not sure quite why that is at the moment so I will have to investigate this further once I start building, but I suspect it is because the lower notes require less energy to make them sustain.

I briefly mentioned this in N Ellingworth's Building a Guitar thread and thought I'd open a new thread for this subject.

The idea is to build an Infinity Sustainer for my guitar, this is basically an E-Bow type device fitted into the body near the neck that excites all six strings. This is not a new idea, it was mentioned in E-Bow's original patent application and Fernandez and Kramer built several guitars with built-in sustainers, but they are expensive.

Since this project involves modifying the guitar (and I don't know whether it will work yet) I am going to be making these mods to a cheap Fender Squier.

Actually, My friend's Jackson is actually really good value for money, not actually an expensive guitar at all, but I compare to the Fernandes guitars, as I'm pretty sure you can't get them here in Australia and I believe the Kramer guitars fitted with Sustainers are out of production.

This is a fantastically cool idea. Let me know how it works out, I'd like to try it someday!

Actually I think it would fit in really well with my band's sound. I play bass with an ebow a lot.

Anyway, instead of worrying about damping the strings, maybe alternate tunings could produce some sweet chords.

Also, will this gizmo have an on/off switch or will it be a full time thing? If I were building it, I'd drill a hole for a small toggle switch. Speaking of which, is this sustainer pickup system active? Also, a bright blue LED is the crucial (and cheap) addition to any DIY project.

This is a fantastically cool idea. Let me know how it works out, I'd like to try it someday!

Actually I think it would fit in really well with my band's sound. I play bass with an ebow a lot.

Anyway, instead of worrying about damping the strings, maybe alternate tunings could produce some sweet chords.

The Fernadez website has a demo using chords, I don't see any reason why this can't play chords too.

However, on reflection, it would be better with a hex-pickup (like a MIDI pickup) and hex-driver, (i.e. 1 sustainer per string), but that's also 6 times the electronics which would reduce battery life. Also, I'd rather get this version working first

GoldenSpiral wrote:

Also, will this gizmo have an on/off switch or will it be a full time thing? If I were building it, I'd drill a hole for a small toggle switch.

I've bought a volume pot with a built-in on/off switch.

GoldenSpiral wrote:

Speaking of which, is this sustainer pickup system active?

It can be, but not in this version - it has a pre-amp for the pickups but it is bandwidth limited so wouldn't be much use - the O/P jack bypasses the pre-amp.

It is something to think about in the future, but since I'm keeping the standard Squier pickups, their o/p doesn't call for an active drive.

GoldenSpiral wrote:

Also, a bright blue LED is the crucial (and cheap) addition to any DIY project.

Ha! No. At the moment the LED is amber, (used up all my spare blue LEDs on othe DIY projects ) but since the drive amp is linear (ie not class-D) it doesn't produce enough voltage to light the LED more than a glimmer.

Found a source of small neodymium magnets so ordered some to play with - unfortunately from Germany (this is turning into quite a transcontinental project) so they haven't arrived either.

Found a huge ceramic bar magnet at home and wound a small coil around it so I could test the electronics:

I haven't opened up the guitar yet, so I am using an Alesis NanoCompressor (in bypass mode) to split the output from the guitar jack in two - one side to the practice amp the other to the sustainer circuit. The chromatic guitar tuner above is just a double check that it is the guitar that is sustaining and not just the circuit oscillating. The circuit board with the amber LED is the drive amp, the other is a small pre-amp/filter. I can make the LED burn a bit brighter by using a transistor to switch it, but that is way down the "to do" list.

Well, it works. Not great, but at least it makes some kind of effect. The bar-magnet is far to powerful and messes with the pickups if you hold it too close to them, but holding it near the strings at Fret-12 seems okay (but not practical). I guess I'm going to have to wait for the postman now...

It has the same features as the Sustainiac brand sustainer driver it seems.

My guess is that when it is used as a neck pickup alone, it sounds different to the Sustainiac pickup in the neck, but from what I've read, they aren't that much different sounding when used as a stand alone pickup.

Strange that nobody yet pointed out this particular point I'm about to make. It sounds like you have read a lot about the sustainer, but it doesn't sound like you actually used one before (Correct me if I'm wrong please). There is a reason why it goes in the neck pickup, and not the middle or bridge.

A lot of people have been asking over the years 'can I put it in the middle position instead? I really like the sound of my neck pickup and want to leave it that way'. The answer is, you simply can't put anywhere else except for the neck position.

The sustainer driver needs to be as far as possible from the pickup.

It's just like, putting a microphone too close to the speaker of a PA, it feedbacks, and of course just like putting a pickup (a microphone) too close to the amp speakers.

Another reason it needs to be in the neck, is because the harmonic mode will produce the best harmonics in the neck position.

You cannot post new topics in this forumYou cannot reply to topics in this forumYou cannot delete your posts in this forumYou cannot edit your posts in this forumYou cannot create polls in this forumYou cannot vote in polls in this forum